1. Field of Invention
The present invention relates to a parking brake system which is operable by manually operating a brake operating member by a driver, and operable by automatically operating the brake operating member by a brake operating drive source.
2. Description of the Related Art
Conventional parking brake systems for a vehicle are manually operated by a driver by depressing a brake pedal or by manually operating a brake lever.
If the parking brake system is designed to be operated electrically, it is possible to automatically operate the parking brake system by detecting operational conditions, such as by a signal to eliminate or reduce labor for driver operation and simplify driving operation.
In an arrangement in which the brake pedal is connected to an electric motor to enable automatic operation, however, a problem is encountered that, when the brake pedal is to be manually operated, the motor is externally rotated by a depression force on the brake pedal, and for this purpose, a large depression force is required, resulting in a reduced operability.